Oracle Updated 1z0-071 Exam Questions and Answers by jago

A. True. This statement will work if customer_id is a character data type in the database. Oracle will implicitly convert the numeric literal 0001 to a string to compare with customer_id.

D. True. If the insert_date is of type DATE and the NLS_DATE_FORMAT matches 'DD-MON-YY', Oracle will implicitly convert the string literal '01-JAN-19' to a date type to compare with insert_date.

B is incorrect because if customer_id is a numeric data type, there is no need for implicit conversion. C is incorrect because using the DATE literal DATE '2019-01-01' is an explicit conversion. E is incorrect because TO_CHAR(customer_id) is an explicit conversion from a numeric to a string data type.

The statement true regarding the CREATE TABLE command:

C. The NEW_SALES table would not get created because the column names in the CREATE TABLE command and the SELECT clause do not match: The SQL command tries to create a table with columns prod_id, cust_id, and order_date, but the SELECT statement specifies columns prod_id, cust_id, and time_id. The mismatch in column names and the number of columns specified will prevent the table from being created.

Incorrect options:

A: It is possible to specify a DEFAULT value in the column definition when creating a table with the CREATE TABLE AS SELECT syntax.

B: Not all NOT NULL constraints (or any other constraints, for that matter) are automatically passed to the new table unless explicitly stated in the CREATE TABLE statement.

D: FOREIGN KEY constraints are not automatically included when creating a table using the CREATE TABLE AS SELECT syntax; they would need to be added explicitly afterwards.

Single-row functions operate on single rows and return one result per row. Let's look at each option in the context of Oracle 12c SQL:

A. CONCAT: This function can only combine two values at a time. If you need to concatenate more than two values, you have to nest CONCAT functions or use the || operator.

B. MOD: The MOD function returns the remainder of a division operation, not the quotient.

C. CEIL: This function returns the smallest integer that is greater than or equal to a specified number. It works with both positive and negative numbers.

D. FLOOR: It returns the largest integer that is less than or equal to the specified number, not greater than or equal to.

E. TRUNC: This function can indeed be used with both NUMBER and DATE values to truncate them to a specified number of decimal places or to a particular component of a date.

References:

Oracle Database SQL Language Reference 12c Release 1 (12.1), Functions

Oracle Database SQL Language Reference 12c Release 1 (12.1), CONCAT Function

Oracle Database SQL Language Reference 12c Release 1 (12.1), MOD Function

Oracle Database SQL Language Reference 12c Release 1 (12.1), CEIL and FLOOR Functions

Oracle Database SQL Language Reference 12c Release 1 (12.1), TRUNC Function

A: Incorrect because the CROSS JOIN of the BRICKS table with itself will produce more than one row.

B: Incorrect because CROSS JOINing a table with four rows with itself produces 16 rows, but the WHERE condition filters these down.

C: Incorrect because while a CROSS JOIN of a table with four rows with itself produces 16 rows, this answer does not take into account the WHERE condition.

D: Correct. The CROSS JOIN will result in 16 combinations (4x4), but the WHERE condition b1.weight < b2.weight will only be true for combinations where the second weight is greater than the first. Since there are 4 distinct weights, there are (42)=6(24​)=6 combinations where one weight is less than the other.

E: Incorrect because this does not account for the conditions specified in the WHERE clause.

F: Incorrect because the query will return some rows due to the condition specified.